WhatsApp Messanger: Boon for Mobile Texters!!

If you want some application that will send messages through your mobile free of cost then WhatsApp messanger is the answer for this. It is a cross-plattform mobile messaging application which allow us to exchange messages without having to pay for messages. WhatsApp uses the save internet data plan thet we use for email and web browsing, thus there is no cost to message and stay in touch with our friend.
Also, we can create groups, send each other unlimited images, video and audio messages. The WhatsApp application is available for iPhone, BlackBerry, Android, Windows Phone and these phones can all message each other.

System Requirements:

iPhone
Compatible with iPhone.
Requires iOS 3.1 or later

Blackberry
BlackBerry OS 4.6 or above
BlackBerry Internet Service (BIS) or BlackBerry Enterprise Service (BES)

Nokia
Minimum requirements:
Unlimited data plan!
Nokia Series 40 phone.
Nokia S60 3rd edition, 5th edition, Symbian^3,
Symbian Anna, or Symbian Belle Operating System

Supported devices:
Nokia C3-00 · Nokia C3-01 · Nokia X2-01 · Nokia X3-02 · Nokia X2-00
Nokia Asha: 201 · 300 · 302 · 303 · 306 · 311
Symbian: X7 · E6 · N8 · C6 · C7 · E7 · 500 · 600 · 603 · 700 · 701 · 808
S60 5th edition: Nokia 5800 · Nokia 5530 · Nokia 5230 · Nokia 5233
Nokia 5235 · Nokia N97 · Nokia N97 mini · Nokia X6 · Nokia X5-01 · Nokia C6
Nokia C5-03 · S60 3rd edition: Nokia 5700 · Nokia 6110 · Nokia 6120 · Nokia 6121
 Nokia 6124 · Nokia 6700 · Nokia 6290 · Nokia E51 · Nokia E63 · Nokia E66
 Nokia E71 · Nokia E90 Communicator · Nokia N76 · Nokia N81 · Nokia N81 8GB
Nokia N82 · Nokia N95 · Nokia N95 8GB · Nokia 5320 · Nokia 5630 · Nokia 5730
 Nokia 6210 · Nokia 6220 · Nokia 6650 fold · Nokia 6710 Navigator · Nokia 6720
 Nokia 6730 · Nokia 6760 Slide · Nokia 6790 Surge · Nokia C5 · Nokia E52
 Nokia E55 · Nokia E72 · Nokia E73 · Nokia E75 · Nokia E5 · Nokia N78
 Nokia N79 · Nokia N85 · Nokia N86 8MP · Nokia N96

Unsupported carriers:
C3-00 devices on Telcel in Mexico (please go here for more info)
Vodafone in Portugal
VIVO in Brazil
Claro in Argentina
Airtel, Idea, Vodafone, Tata Docomo and possibly others in India

Windows
Requirement:
Windows Phone 7.5 or higher

App requires:
location services
data services
microphone
music and video library
push notification service
phone identity
camera
contacts
camera

Download link:
http://www.whatsapp.com/download/